Relax. Don't worry about everyone breaking your stones.
Kevin is "right on" if you would like to meet Gary in person one on one.
In the event you cannot go as Kevin suggested, the second alternative would be to contact the MLB office as Nate suggested. Due to security, do not expect MLB or HR to give you any contact information whatsoever. The best you can hope for probably, is that they pass your request to Cederstrom and for Cederstrom to contact you. Make sure you leave all possible ways to contact you personally. There is definitely someone at MLB that could step in and help you without contacting Cederstrom since this would probably get forwarded to people under Baseball Operations of which Joe Torre is responsible. Randy Marsh is director of umpiring and could easily answer your question as could Rich Rieker who runs the camps Kevin was talking about. They could get an answer for you, since, as former umpires they probably keep up with the equipment.
Just googling around, here is another alternative.
A third alternative is to contact the World Umpires Association. The address is PO Box 394, Neenah, WI 54954. You can go online to www.worldumpires.com and contact them by email. Once again, do not be expecting a direct contact with Cederstrom. They can pass along your information to him and leave it up to him to contact you. They may just find out the information for you by contacting Cederstrom and then passing the information to you.
Good luck.
Alright thank you.